How Aggressive Is Your Canine?

By Kim Boatman

When Aleta Watson’s 1-year-old grandson, Xavier, tried to crawl on Aggie, her golden retriever, during Watson’s recent visit to Portland, Ore., there were no worries. The large, imposing dog simply got up and walked away, says Watson. “We love golden retrievers because they tend to be so mellow,” says Watson, 62, a writer based in Ben Lomond, Calif. “Aggie is our fourth purebred golden, and she’s really easygoing. We’ve never seen any sign of aggression in her or our previous goldens.”

A recent study backs up Watson’s experiences with golden retrievers. Evaluating surveys of two groups of owners, researchers at the University of Pennsylvania’s Center for the Interaction of Animals and Society rated dog breeds on their levels of aggression. The study, accepted for publication in the journal Applied Animal Behaviour Science, indeed found that goldens rate among the least aggressive breeds. But the study also offers somewhat unexpected conclusions when it comes to canine feistiness. You might be surprised to find where your dog’s breed ranks.

Small Dogs, Big AttitudesUsing a survey called the C-BARQ (Canine Behavioral Assessment and Research Questionnaire), researchers collected results from both online respondents and a sampling of members of 11 breed clubs recognized by the American Kennel Club. Remember the saying “It’s not the size of the dog in the fight but the size of the fight in the dog”? It turns out the surveys found two small dog breeds, Chihuahuas and dachshunds, rated high on aggression toward both humans and other animals.

“Initially, I was quite surprised by how aggressive these smaller breeds came out,” says Dr. James Serpell, study co-author and director of the Pennsylvania center. “In smaller dogs, I think we tolerate higher levels of aggressive behavior,” he says, adding, “the prospects of being seriously injured by a Chihuahua are small. Part of the problem with these little dogs is that they probably do live in terror a lot of the time because they are so small, and they are surrounded by giants -- both humans and dogs.”

“Interdog aggression is scarily high in some breeds,” says Dr. Serpell. “Close to 30 percent of Akitas, for example, had shown serious aggression toward other dogs in the recent past,” says Dr. Serpell. Indeed, says co-author Dr. Deborah Duffy, the amount of dog-versus-dog aggression reported by owners was alarming.

“What surprised us most was the percentage of owners reporting that their dog had bitten or tried to bite other dogs,” says Dr. Duffy. “When we think of canine aggression from a public health perspective, aggression toward humans is typically what gets discussed. However, our study found that serious aggression among dogs is surprisingly common for some breeds, and this also presents a public health hazard because people can get bitten trying to separate dogs that are fighting.”

Genetics likely plays a role in the aggressiveness of breeds such as the Akita, says Dr. Serpell. However, the researchers point out that these aggressive traits are often balanced by positive attributes, such as loyalty. Aggressive dogs, even the tiniest ones, tend to make terrific watchdogs, letting us know when strangers are around.

Nature or NurtureNagja Bamji says that her dachshund, Ronny, is far from aggressive. Ronny gives other dogs a wide berth, loves kids and recently backed off when a squirrel hissed at him, says Bamji, 46, a homemaker in Fremont, Calif. You also might find that your dog doesn’t fit the profile developed in this study.

“We do have breed differences; there is no question,” says Dr. Gail Clark, a canine behavioral psychologist based in Fort Collins, Colo. “But there is a tremendous amount of factors in dog behavior.”

She explains that environment and training, as well as breed, help determine how your dog behaves. For example, she says, the owners of little dogs tend to pick them up frequently in threatening situations. Perched high in their owners’ arms, the little dogs feel mighty brave. When the dogs return to the ground, they might feel defensive and threatened. How you perceive your dog’s breed, regardless of size, might therefore influence the way you train or handle your pal, thus affecting your canine’s long-term behavior, says Dr. Serpell.

Where you obtain your puppy can be another significant factor, says Dr. Serpell, who recommends finding a reputable breeder, visiting the breeder and even meeting your pup’s parents, if possible. Dogs produced in puppy mills often have behavioral problems, he says. Puppies tend to be removed from their mothers and littermates too soon, and they don’t have enough positive human contact in their early weeks. Their mothers often are kept in highly stressful environments during their pregnancies, which likely has a longstanding impact on the puppies, says Dr. Serpell.

Individuality Can Overcome Statistics Dr. Serpell believes that the next step for researchers is to understand the factors that contribute to individual dogs behaving aggressively. When it comes to this study, it’s important to not paint every dog with the same brush, he thinks. “The No. 1 thing we’d like you to take from the study is it’s based on breed averages,” says Dr. Serpell. “Branding a breed as dangerous or aggressive is inappropriate. Within any breed, you’re going to find many, many individuals that are really nice and well-tempered.”

If you’re interested in evaluating your dog’s behavior, you can still take the C-BARQ. The survey, which takes 10 to 15 minutes to complete, is located on the University of Pennsylvania’s School of Veterinary Medicine Web site.

Kim Boatmanis a journalist based in Northern California. She is also the managing editor of ExceptionalCanine.com. Boatman's work has appeared in TheMiami Herald, the Detroit Free Press and the San Jose Mercury News. She is a lifelong lover of animals, and a frequent contributor to The Dog Daily.

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Posted on July 9, 2011

HarryMoe says: I have had 2 Boxers,best Dogs ever.Instinctively protect children and know a bad guy when they smell them

Posted on February 13, 2009

Victoria says: In response to the German Shephers who destroys everything.Lots and lots of chew toys work. Big rope bones, go to your local butcher and ask for some marrow bones. They get bored when you go to work so they stress, then chew everything. G.Shepherds are my passion I've had 4 and it's been the same with all 4.

Posted on September 21, 2010

Linda says: I would like to get a friend for Cody my 7 yr old English Springer Spaniel. We recently lost our Chocolate Lab and are now looking for another dog to play with our sweet Cody. He loves people and seems to get along with other dogs.

Posted on September 28, 2010

Denyce says: I made the mistake of getting 2 littermates, M & F. Separated they are AMAZING 5 mo old pups: Know basic commands i.e. sit, down, stay, leave it, come (almost) and are crate trained. Housetraining is going very well! On and off leash they are great - but not together. Both are spaye/neutered yet are fighting to establish "alpha" btw themselves? Hinesight tells me I never should have taken 2 littermates on at one time. They can start to depend upon each other, instead of the owner, etc. Before it becomes too difficult for my family, we sadly must re home Gucci, the female. She is absolutely beautiful, still cuddle-bug in a blanket and VERY smart. Gucci learned her DOWN command in 1/2 day! I live in NH. *A puppy is a huge responsibility, a lifelong but so rewarding commitment. Contact me w/ any questions. I have only had these guys for 10 weeks.

Posted on November 12, 2008

ANGELA says: I have soon to be 1 yr old german shepherd female who constantly breaks everything, from toys to walls to scratching the basement concrete wall. what should i do? how can i stop her from doing this?

Posted on December 13, 2008

mike siroky says: Kim has always been a good writer. You are lucky to have her

Posted on January 27, 2009

cheeptickets says: Very nice site. I enjoy your webcam the most. Beautiful scenery! Keep up the great work.

Posted on February 3, 2009

phyllis lusk says: I have two Shia Tsus, one, Max, is gentle and afraid of everything, the other one, Chewie, is sweet until you do something he doesn't like, then he'll bite without warning. I got the first one as a small pup, the second one was a rescue when he was 2 1/2 years old. He came from a family with 3 small boys who rough housed with him and I'm sure teased him. He hoards treats, is very possessive with anything he perceives to belong to him and gets nasty if anyone even walks close to his "stuff". He will not back down no matter what. He's very good with other animals but with people he's unpredictable. When I scold him, the other one, Max, will chastize him and only then will he will show submission.
Any suggestions?

Posted on November 6, 2008

EFord says: I appreciate the fact that the study includes the difference between dog-dog agression and dog-human agression. We had, until recently, a wonderful Akita and a Pem Corgi. The Akita was VERY well trained and socialized from 7 weeks; the "nurture" part was well planned and executed. At her peak of training, she could be off-leash in dog-parks safely. But her "nature" was definitely agressive to dogs who were not part of her pack. On the other hand, she was safer than the Corgi in terms of human agression.
I wouldn't brand breeds as bad, but I would suggest that some breeds are absolutely not beginner's dogs, and will require LOTS of well-structured work to live safely within humans' expectations in a human world. If not, occasionally horrible things happen to others; often, the dog itself is killed for acting according to it's nature.

Posted on October 10, 2008

NELLE says: i do appreciate this comment:Branding a breed as dangerous or aggressive is inappropriate. Within any breed, you

Posted on October 29, 2008

I Carrillo says: Your Border Collie may be quite bored. This is a working breed and needs an active job to do. There are even ways to join a herding training program for you and your dog, where the dog learns to pay attention to new commands and herd sheep. Even if the only exposure to this activity is during the training, the dog's natural instinct to focus and work is taken care of. Toys that keep your dog active even when you are not around will help...

Posted on November 3, 2008

Gail Shipper says: I rescued a 4-year-old chihuahua, and need to socialize her with a 10-month-old puppy chihuahua. The puppy just wants to play with the 4-year old, and is very friendly with all other dogs. The 4-year old is very agressive towards the puppy...growls at her and attempts to bite her. What can you suggest that I do to make the dogs friendly with each other.
I would appreciate any help I can get!! Thanks, Gail Shipper

Posted on September 26, 2008

AL JOHNSON says: The article is right on about puppy mill dogs. We bought out a breeder and she is so traumatized that she will freak out trying to get away from me and often wets the floor if I get too close. Treats don't work in this situation, no apetite. It may take a few years of pleasant routine and daily exercise to get her out of her shell. Meanwhile she is very dependant on my wife. I did hear an interesting answer on the bark on TV. Allow them to bark once to announce a visitor and get up to see with them. If they continue barking, sit back down and ignore them. They are barking to get your attention.

Posted on October 10, 2008

NELLE says:

Posted on September 22, 2008

Daphne Robert-Hamilton, CPDT says: Trying to understand behavior is important and I'd like to add that behavior should be looked at from a behavioral perspective such as mentioned in James O'Heare's book The Dog Aggression Workbook. It's good to know about breed tendencies but more importantly to treat every individual and case as unique situation and determine the antecedents that drive the behavior and the consequences for that behavior. Check out the behaviorology website.
Just want people to look at behavior from a behavior perspective and not to label or target certain breeds in a general category.
Cheers,

Posted on September 23, 2008

Michelle says: I have a 7 yr old Border Collie that barks at every little noise. It seems to be getting worse each year. I have tried breaking his concentration with a loud noise followed by a no but it doesn't work. Does any one have any suggestions?

Posted on September 26, 2008

stuart says: although not rated as a pure breed these are the sweetest little pocches around. they love everyone, adults and kids alike and other pets. the worst they will do to anyone is lick a face as often as you would like!!!!!!!
they are extra sweet little dogs